Validity and reliability of the Turkish version of the Health Assessment Questionnaire for the Spondyloarthropathies

The Health Assessment Questionnaire for Spondyloarthropathies (HAQ-S) was built by adding five new questions related with cervical and lumbar spine functions to HAQ by Daltroy et al. (in J Rheumatol 17(7):946-945, 1990). The aim of this study was to adapt the added five items into Turkish and then to test its reliability and validity. New questions were adapted to Turkish according to 'translation-back translation' method. Seventy-nine patients with ankylosing spondylitis were asked with the Turkish version of HAQ-S (HAQ-S TV). To assess, construct validity patients were evaluated by HAQ, Bath AS Functional Index (BASFI), Bath AS Disease Activity Index (BASDAI), Bath AS Metrology Index (BASMI), Maastricht AS Enthesitis Score (MASES), Ankylosing Spondylitis Quality of Life (ASQoL), and laboratory variables (erythrocyte sedimentation rate, C-reactive protein). Construct validity was investigated with Spearmann's rank correlation coefficient. Reliability of HAQ-S TV was assessed by internal consistency. Inter- and intra-observer reliability were tested with Cronbach's alpha score. HAQ-S TV met set criteria of reliability and validity. Reliability of adapted version was found good with high internal consistency value. (Cronbach's alpha = 0.89). In addition to this intra-observer and inter-observer reliability were found adequate for total score of HAQ-S (Cronbach's alphas: 0.999 and 0.998 in order) and also for each added five questions (Cronbach's alphas > 0.7). Positive correlations were found between HAQ-S TV and HAQ, BASFI, BASDAI, BASMI, MASES, ASQoL, ESR, and CRP (P < 0.05). The results of this study showed that HAQ-S TV was reliable and valid in patients with AS.